1. Field of the Invention
The present invention relates to a disengagement mechanism for a friction clutch in a motor vehicle, wherein the friction clutch is arranged between an internal combustion engine and a transmission connected to the internal combustion engine by a casing and the friction clutch is rotatable about an axis.
2. Description of the Related Art
German reference DE-OS 23 22 247 discloses a self-centering release bearing which is held in frictional contact at a clutch lever so as to be displaceable radially by a plurality of spring clamps. The spring clamps also fix a guide sleeve which slides on a guide pipe between the release bearing and the clutch lever.
British reference GB-2 046 359 A discloses a release bearing whose guide sleeve can be snapped onto a release lever when installed in the vehicle by locking pins which are formed integral with the guide sleeve.
French reference FR-2 577 291 discloses a self-centering release bearing arrangement in which the release bearing, the guide pipe and a pressing disk are preassembled by a clamping ring. The pressing disk is contacted during operation by a clutch fork that is separately mounted.
U.S. Pat. No. 4,648,500 discloses a mechanism of the type mentioned above in which a release bearing arrangement, a clutch lever and a guide sleeve are prepared separately from one another and are first joined upon installation in the vehicle.
In previous solutions, the individual components or component groups of the clutch disengaging mechanism were assembled only during the course of connecting the transmission to the engine. This made warehousing of the individual parts and assembly more difficult. In the event of a faulty positioning of the individual parts relative to one another, the transmission had to be separated from the engine again to correct the defective installation.
To compensate for axial play in the individual component parts of the disengaging mechanism in the operation-ready state, it is conventional to provide a preloading spring which pretensions the clutch lever relative to the friction clutch. The preloading spring is commonly integrated in the hydraulic slave cylinder of the disengaging mechanism which is to be mounted subsequently. It has also been attempted to install the preloading spring between the clutch lever and the casing. However, this requires separate means for securing or holding the assembly in place during installation. The means for securing would have to be introduced from the outside through an opening in the casing. After completion of the assembly of the preloading spring and the clutch lever, the opening must be resealed by, for example, a rubber cap.